A number of toothbrush structures have been created over the years providing a variable head configuration whereby the bristles arrangement or relative heights is altered to facilitate different brushing requirements.
U.S. Pat. No. 3,683,442 issued to James A. Holly on Aug. 15, 1972 sets forth a toothbrush having a plurality of individual brush elements which are spring biased into an upright position and which adapts to configure the brush to conform to the tooth surfaces.
U.S. Pat. No. 726,716 issued to D. F. Maher on Apr. 28, 1903 sets forth a toothbrush having a moveable center row of bristles supported within a center groove by a guide strip.
U.S. Pat. No. 4,488,328 issued to Richard M. Hyman on Dec. 18, 1984 sets forth a toothbrush having a floating head structure in which a yoke structure supports an elongated brush head by means of a resilient element which spring biases the pivotal motion of the elongated head element.
U.S. Pat. No. 4,633,542 issued to Bernard Taravel on Jan. 6, 1987 sets forth a brush having resiliently retractable bristles in particular for brushing surfaces of complex shapes such as teeth. A plurality of bristle tufts are resiliently retractable by thrusting against a membrane which is capable of resilient deformation. Each tuft is independently moveable with respect to the other tufts within the brush such that the combination of tufts adapts to the shape of the surface to be brushed.
U.S. Pat. No. 2,266,195 issued to R. L. Hallock on Dec. 16, 1941 sets forth a toothbrush having a center portion of the head being independently moveable with respect to the remaining portions of the brush head and being coupled to the handle by a resilient beam spring member.
U.S. Pat. No. 3,082,457 issued to F. R. Lucibello et al on Mar. 26, 1963. A self adapting tuft for brushes is set forth in which a plurality of recesses within the toothbrush head receive a corresponding plurality of brush tufts which are supported within the recesses by a resilient membrane and which permit the individual tufts within the brush head to move in order to accommodate the shape of the structure being brushed.
U.S. Pat. No. 2,435,394 issued to J. P. Hawley on Feb. 3, 1948 for an adjustable toothbrush sets forth a toothbrush having a moveable center row of bristles, the lateral position of which may be adjusted to be aligned with or offset from the remaining bristle structures in the toothbrush head.
U.S. Pat. No. 2,706,825 issued to A. R. Blakeman on Apr. 26, 1955 for a toothbrush sets forth a toothbrush having a removeable bristle structure supported upon an elastic deformable flexible bristle membrane.
U.S. Pat. No. 2,443,297 issued to L. R. Bressler on June 15, 1948 for a toothbrush in which the head structure is segemented and which is secured to the handle by a resilient spring member. U.S. Pat. No. 2,864,111 issued to C. Rotceig on Dec. 16, 1958 sets forth toothbrushes in which a flexible head structure insert supports a plurality of bristle tufts and which is deformably secured within the head.
U.S. Pat. No. 4,140,452 issued to San Bau Jean on Dec. 23, 1980 sets forth an elastic base toothbrush in which a toothbrush head defines a recess supporting a plurality of elastic members and an overlying bristle structure. The elastic members deform during the brushing process and permit the bristles to flex in use and thereby conform to the surface being brushed.
While the foregoing described prior art toothbrushes provide some benefits of variably configured heads, they are often difficult to manufacture and are equally often difficult to operate in use due to the complexities of the mechanisms used to configure the toothbrush heads.
One structure set forth in U.S. Pat. No. 4,409,701 issued to Robert Perches on Oct. 18, 1983 sets forth a toothbrush having a center bristle arrangement which is elevated by a slideable wedge.